A news release from the Story County Sheriff's Office says inmate Glenn Smith complained of chest pains around noon Saturday. Jail staff began treating Smith when he became unconscious and unresponsive.

CPR was started, and Smith was taken by ambulance to Story County Medical Center, where he was pronounced dead shortly after 1 p.m. Officials say it appears Smith died from a massive heart attack.

An investigation into the death is being conducted by the Story County Sheriff's Office.

Smith was scheduled to be sentenced Monday for the 2008 death of another homeless man at a transient camp in Ames.